TW202407302A - Optical sensor system, method, and optical sensing array for in-situ optical chamber surface and process sensor - Google Patents

Abstract

Embodiments disclosed herein include optical sensor systems and methods of using such systems. In an embodiment, the optical sensor system comprises a housing and an optical path through the housing. In an embodiment, the optical path comprises a first end and a second end. In an embodiment a reflector is at the first end of the optical path, and a lens is between the reflector and the second end of the optical path. In an embodiment, the optical sensor further comprises an opening through the housing between the lens and the reflector.

Description

Optical sensor systems, methods and optical sensing arrays for in situ optical chamber surface and processing sensors

Embodiments are related to the field of semiconductor manufacturing, and particularly to systems and methods for providing in-situ optical sensors for monitoring chamber surface conditions and chamber processing parameters.

Changes to the chamber surface affect various processing parameters. For example, redeposition of etch byproducts on chamber walls can alter the etch rate for a given process. Accordingly, when substrates are processed in a chamber, etch rates (or other processing parameters) can change and cause non-uniform processing between substrates.

To account for changes in processing conditions, optical emission spectroscopy (OES) has been implemented in the processing chamber. OES involves monitoring the emission spectrum of the plasma in a chamber. A window is placed along the chamber wall and the emission spectrum can be passed along an optical path through the window to a sensor outside the chamber. As the plasma spectrum changes, a qualitative analysis of the processing operation can be inferred. In particular, OES is useful for deciding when the endpoint of a processing operation has been met. To provide optimal measurements, the window is designed to prevent deposition along the optical path. Furthermore, although endpoint analysis is possible, there is currently no process for performing quantitative analysis using existing OES systems.

Embodiments disclosed herein include optical sensor systems and methods of using such systems. In one embodiment, an optical sensor system includes a housing and an optical path passing through the housing. In one embodiment, the optical path includes a first end and a second end. In one embodiment, a reflector is located at the first end of the optical path, and a lens is located between the reflector and the second end of the optical path. In one embodiment, the optical sensor further includes an opening through the housing between the lens and the reflector.

In one embodiment, a method for measuring a processing condition or a chamber condition in a processing chamber using an optical sensor includes the following steps: acquiring a reference signal. In one embodiment, obtaining the reference signal includes emitting electromagnetic radiation from a source external to the chamber, wherein the electromagnetic radiation is propagated along an optical path between the source and a reflector in the chamber. electromagnetic radiation; using the reflector to reflect the electromagnetic radiation back along the optical path; and using an inductor to sense the reflected electromagnetic radiation, the inductor being optically coupled to the optical path. In one embodiment, the method further includes the step of obtaining a processing signal, wherein the step of obtaining the processing signal includes the step of using the sensor to sense electromagnetic waves emitted in the processing chamber traveling along the optical path. radiation. In one embodiment, the method further includes the step of comparing the processed signal with the reference signal.

In one embodiment, an optical sensing array for a plasma processing chamber includes a plurality of optical sensing systems oriented around a perimeter of the processing chamber. In one embodiment, each of the plurality of optical sensing systems includes: a housing; an optical path passing through the housing, wherein the optical path includes a first end and a second end; a reflection a reflector located at the first end of the optical path; a lens located between the reflector and the second end of the optical path; and an opening between the lens and the reflector through the shell.

The systems and methods described herein include optical sensors for in-situ monitoring of chamber conditions and/or process conditions within the chamber. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the embodiments. It will be apparent to one of ordinary skill in the art to which this invention pertains that the embodiments may be practiced without these specific details. In other instances, well-known aspects have not been described in detail so as not to unnecessarily obscure the embodiments. Furthermore, it is to be understood that the various embodiments illustrated in the drawings are diagrammatic representations and are not necessarily drawn to scale.

As mentioned above, currently available optical emission spectrometry (OES) systems can provide qualitative measurements for functions such as endpoint determination, but are currently unable to provide precise quantitative measurements. Existing OES systems cannot directly measure process parameters such as etch rate. Accordingly, embodiments disclosed herein include an optical sensor system including an optical path through which both a reference signal and a plasma emission spectrum pass. For example, the optical path starts from the light source, passes through the chamber wall, and reflects off the reflector surface along the optical path toward the sensor. Since the reference signal and emission spectrum pass along the same optical path, the reference signal can be used to determine the losses attributable to the optical path without opening the chamber and interrupting operation. This allows precise and quantitative measurement of the emission spectrum. From this, calibrated plasma emission spectra can be used to determine process parameters such as etch rate.

Additionally, while currently available OES systems are designed to prevent deposition along the optical path, embodiments disclosed herein include reflector surfaces that are exposed to the processing environment. In some embodiments, the reflector surface may be selected to substantially match the interior surface of the chamber. In this way, the deposition on the reflector surface is substantially similar to that seen on the interior surface of the chamber. The reflector surface interacts with the electromagnetic radiation emitted by the source and can therefore be used to determine the properties of the deposited film or wall material conversion. For example, absorption of a portion of the spectrum of electromagnetic radiation may be related to a specific material composition and/or thickness of the film.

Accordingly, embodiments disclosed herein allow for quantitative in-situ measurements of process conditions and/or chamber conditions. Because the embodiments disclosed herein provide quantitative measurements, embodiments may allow chamber matching measurements (ie, comparison of a single process performed in different chambers). In some embodiments, a single optical sensor may be included in the processing chamber. Other embodiments may include arrays of optical sensors placed around the perimeter of the processing chamber. These embodiments may allow the acquisition of chamber uniformity information (eg, plasma uniformity, chamber surface uniformity, etc.). Additionally, these embodiments may also provide indications of chamber anomalies (eg, chamber drift).

Referring now to FIG. 1 , a cross-sectional view of a processing tool 100 is shown according to an embodiment. In one embodiment, processing tool 100 includes chamber 105 . For example, chamber 105 may be suitable for low pressure processing operations. In one embodiment, processing operations may include generating plasma 107 in chamber 105 . In one embodiment, substrate support 108 is located in chamber 105 . Substrate support 108 may be a chuck (eg, electrostatic chuck, vacuum chuck, etc.) or any other suitable support upon which one or more substrates may be placed during processing.

In one embodiment, the processing tool 100 may include an in-situ optical sensor 120 . The in-situ optical sensor 120 passes through the surface of the chamber 105 such that a first portion of the optical sensor 120 is inside the chamber 105 and a second portion of the optical sensor is outside the chamber 105 . In one embodiment, optical sensor 120 is illustrated through the side wall of chamber 105 . However, it should be understood that the optical sensor 120 may be positioned to pass through any surface of the chamber 105 .

In the illustrated embodiment, a single optical sensor 120 is shown. However, it should be understood that embodiments are not limited to such configurations and that more than one optical sensor 120 may be included in the processing tool 100 . Furthermore, optical sensor 120 requires only a single optical opening (ie, window) through chamber 105 . As will be described in more detail below, the optical path includes a reflector 121 to reflect electromagnetic radiation from source 137 back through the same opening. This is in contrast to existing systems, which require an optical path across the space of chamber 105 and require at least two optical openings through the chamber.

In one embodiment, optical sensor 120 includes a housing. In one embodiment, the housing may include a first housing 124 and a second housing 122 . In one embodiment, the first housing 124 may be secured to the second housing 122 using any suitable fasteners. In other embodiments, the housing may be a unitary structure. That is, the first housing 124 and the second housing 122 may be combined into a single structure. Additionally, although first housing 124 and second housing 122 are disclosed, it should be understood that the housings may include any number of components coupled together.

In one embodiment, the first housing 124 may extend through the opening in the chamber 105 and into the chamber interior space. For example, an extension (eg, tube 126) may pass through an opening in chamber 105. In one embodiment, tube 126 may be an optically clear material. For example, tube 126 may be quartz. However, it should be understood that tube 126 need not be optically clear. In some embodiments, tube 126 may be a ceramic or metallic material. Additionally, although tube 126 is depicted, it should be understood that any elongate member may extend into the space of chamber 105 . In particular, any structure capable of supporting the reflector 121 in the interior space of the chamber 105 may be used.

In an embodiment, one or more openings 123 may be placed along the length of tube 126. One or more openings 123 allow electromagnetic radiation from the plasma 107 to enter the optical sensor 120 . Additionally, opening 123 exposes reflector 121 to the processing environment. Exposing reflector 121 to the processing environment allows the surface of reflector 121 to be modified in substantially the same manner as the interior surface of the chamber is modified during processing operations. For example, by-products deposited on the interior surfaces of chamber 105 may also be deposited on reflector 121 . In certain embodiments, reflector 121 may include the same material as the interior surface of chamber 105 . From this, it can be assumed that the surface of reflector 121 changes to substantially match the change of the interior surface of chamber 105 . In this manner, monitoring of the chamber surface can be performed via optical sensor 120 .

In some embodiments, reflector 121 may be a replaceable component. That is, the reflector 121 may be a removable component from the first housing 124 . For example, reflector 121 may be attached to a cap covering the end of tube 126 . Having a removable reflector allows replacement of the reflector 121 after its useful life has expired. Additionally, different reflector materials can be used to match the interior surfaces of the chamber for various processing tools.

In some embodiments, lens 125 may be secured between first housing 124 and second housing 122 . Lens 125 is positioned along the optical path between source 137 and reflector 121 to focus electromagnetic radiation passing along the optical path. In some embodiments, lens 125 may be part of a seal to close the opening through chamber 105 . For example, an O-ring or the like may bear against the surface of lens 125 facing chamber 105 .

In one embodiment, the optical sensor 120 may further include a source 137 and a sensor 138 . Source 137 and sensor 138 may be optically coupled to the optical path. For example, fiber optic cable 132 may extend from second housing 122 . In one embodiment, fiber optic cable 132 may include a splitter 134 that branches to fiber optic cable 135 to source 137 and to fiber optic cable 136 to sensor 138 .

In an embodiment, source 137 may be any suitable source for propagating electromagnetic radiation along an optical path. In particular, embodiments include high precision sources 137 . High-precision source 137 provides a known electromagnetic spectrum that can be used as a reference baseline for measurements using optical sensor 120 . In one embodiment, source 137 may be a single wavelength source. For example, source 137 may be a laser or a light emitting diode (LED). In other embodiments, source 137 may be a broadband light source. For example, source 137 may be an arc flash lamp (eg, a xenon flash lamp).

In one embodiment, sensor 138 may be any suitable sensor for detecting electromagnetic radiation. In one embodiment, sensor 138 may include a spectrometer. For example, a spectrometer may have an array of charge coupled devices (CCD). In other embodiments, the sensor 138 may have photodiodes that are sensitive to specific wavelengths of electromagnetic radiation.

Referring now to FIG. 2 , a cross-sectional view of a three-dimensional illustration of a housing of optical sensor 220 is shown in accordance with an embodiment. As shown, optical path 228 extends through the housing. For example, optical path 228 extends along a channel in second housing 222 , through lens 225 , and through tube 226 of first housing 224 toward reflector 221 . In one embodiment, opening 223 through tube 226 allows electromagnetic radiation from the processing environment (eg, from the plasma) to pass into the housing and propagate along optical path 228 . Opening 223 also exposes reflector 221 to the processing environment inside the chamber. Accordingly, the surface of reflector 221 may be monitored for deposition or other transformations in order to determine changes to the interior surface of the chamber.

As shown in Figure 2, reflector 221 is a cap attached to the end of tube 226. Accordingly, the reflector 221 can be replaced by removing the cover and attaching a second cover to the second reflector 221 . Additionally, FIG. 2 illustrates channel 227 proximate lens 225. In one embodiment, channel 227 may be sized to receive an O-ring (not shown) against first housing 224 and lens 225 . Accordingly, a vacuum seal can be maintained even with openings through the chamber wall.

As shown above with respect to FIG. 1 , the housing of optical sensor 220 may alternatively include a single component or more than two components (ie, more than first housing 224 and second housing 222 ). Additionally, tube 226 may be replaced with any elongated structure that can support a mirror along optical path 228 . For example, tube 226 may be replaced using one or more bundles extending from first housing 224 .

Referring now to FIGS. 3A and 3B , a pair of cross-sectional views depict a process using an optical sensor according to an embodiment.

Referring now to Figure 3A, a cross-sectional view at the beginning of processing of a substrate is shown. As shown, optical sensor 320 is substantially similar to optical sensors 120 and 220 described above. For example, a housing is shown that includes a first housing 324, a second housing 322, a lens 325, and a reflector 321. Reflector 321 is shown floating in Figure 3A. That is, only the opening 323 of the support structure is shown. However, it should be understood that the reflector 321 is connected to the first housing 324 in a configuration out of the plane of the cross-sectional view. For example, one or more beams or tubes may be used to connect reflector 321 to first housing 324.

In one embodiment, the reference signal 341 may be generated by a source (not shown) and optically coupled to the optical path through the housings 324, 322. For example, reference signal 341 may propagate along fiber optic cable 332 before entering housing 322 . Reference signal 341 may then propagate towards reflector 321 and be reflected back along the optical path as reflected signal 342 . Reflected signal 342 may be optically coupled with fiber optic cable 332 and passed to a sensor (not shown).

Since the source emits electromagnetic radiation with a known spectrum and intensity, the sensor's measurement of the reflected signal 342 provides a baseline for losses along the optical path. That is, the difference between the measured value (eg, spectrum and intensity) of the reflected signal 342 and the known spectrum and intensity of the source provides a measure of the losses inherent in the optical sensor 320 . From this, the known losses can be used to calibrate subsequently acquired signals.

In particular, the sensor may also sense electromagnetic radiation emitted by the plasma. For example, the plasma signal 343 may pass through the opening 323 of the optical sensor 320 and propagate along an optical path to the sensor (not shown). The measurement of the plasma signal 343 can then be calibrated by adding back the known losses inherent in the optical sensor. In this way, a quantitative measurement of the electromagnetic radiation emitted by the plasma can be provided.

Referring now to FIG. 3B , a cross-sectional view of optical sensor 320 is shown after disposing membrane 306 over the surface of chamber 305 and over the surface of reflector 321 , according to an embodiment. In one embodiment, membrane 306 may be a by-product of processing operations performed in chamber 305. For example, film 306 may be a redeposition of a by-product of the etching process. In embodiments where the surface of the reflector 321 is of the same material as the interior surface of the chamber 305, the film 306 on the reflector 321 will represent the film 306 on the interior surface of the chamber 305.

Accordingly, optical sensor 320 may also be used to determine one or more properties of film 306. In one embodiment, the reflected signal 342 can be measured to find the difference relative to the reference signal 341 . For example, a reduction in a specific wavelength of the reflected signal 342 (relative to a reference signal) may be used to determine what material was deposited on the film. In particular, certain materials will preferentially absorb parts of the spectrum of reference signal 341 . Accordingly, identifying portions of the reflected signal 342 with reduced intensity allows the composition of the film 306 to be determined. Additionally, changes in reflected signal 342 may also identify film thickness.

Referring now to FIG. 4A , a cross-sectional view of optical sensor 420 through a surface of chamber 405 is shown, according to an additional embodiment. Optical sensor 420 in Figure 4A is substantially similar to optical sensor 320 in Figure 3A except that source 437 and sensor 438 are directly integrated into second housing 422. For example, reference signal 441 can be directed toward reflector 421 through lens 439 and lens 425, and reflected signal 442 and plasma signal 443 can be redirected toward sensor 438 through lens 439. Accordingly, optical coupling of source 437 and sensor 438 to the optical path can be implemented without the need for fiber optic cables. These embodiments may also provide a more compact optical sensor 420.

Referring now to FIG. 4B , a cross-sectional view of optical sensor 420 through a surface of chamber 405 is shown, according to an additional embodiment. Optical sensor 420 in Figure 4B is substantially similar to optical sensor 320 in Figure 3A except for the placement of filter 445 along the optical path. In one embodiment, the filter 445 can provide a specific passband to improve the signal-to-noise ratio and improve the performance of the optical sensor. In one embodiment, filter 445 is placed between lens 425 and the sensor (not shown). That is, the filter 445 is placed outside the chamber space for protection from the processing environment.

Referring now to FIG. 5 , a plan view cross-sectional view of a processing tool 500 is shown in accordance with an embodiment. In an embodiment, processing tool 500 may include chamber 505 . A substrate support 508 (eg, chuck, etc.) may be located within the chamber 505 . In one embodiment, a plurality of optical sensors 520 _A - _E are arranged in an array around the perimeter of the chamber 505 . Optical sensors 520 _A - _E may be substantially similar to one or more of the optical sensors described above. In the illustrated embodiment, five optical sensors 520 _A - _E are shown. However, it should be understood that any number of optical sensors 520 may be included in the processing tool 500 . The use of multiple optical sensors 520 allows the acquisition of uniformity information. For example, plasma uniformity and/or wall condition uniformity may be obtained. Additionally, chamber drift can also be determined.

Referring now to Figures 6A and 6B, shown is a process flow diagram depicting a process of using an optical sensor to provide quantitative measurements in situ, according to one embodiment.

Referring now to Figure 6A, process 660 begins with operation 661 and includes acquiring a reference signal that propagates along an optical path between a reflector inside the chamber and an inductor outside the chamber. Specifically, operation 661 may include process 670 illustrated in Figure 6B.

Referring now to Figure 6B, process 670 may begin with operation 671, including emitting electromagnetic radiation from a source external to the chamber. In one embodiment, electromagnetic radiation propagates along an optical path between the source and a reflector in the chamber. Process 670 may then continue with operation 672, which involves using a reflector to reflect the electromagnetic radiation back along the optical path. Process 670 may then continue with operation 673, which includes sensing the reflected electromagnetic radiation using a sensor optically coupled to the optical path.

Referring back to FIG. 6A , process 660 may then continue with operation 662 , which includes obtaining a processing signal by sensing electromagnetic radiation emitted in the processing chamber propagating along the optical path. In one embodiment, process 660 may then continue with operation 663, which includes comparing the processed signal to the reference signal.

In one embodiment, comparison of the reference signal and the processed signal may provide a quantitative measure of the processed signal. In particular, the reference signal may provide a measure of the losses inherent in the optical sensor. Accordingly, the losses inherent in the optical sensor can be added back to the processed signal to provide a quantitative value to the processed signal. Obtaining quantitative values provides a more accurate picture of the processing conditions in the chamber. Additionally, quantitative values can be compared across different chambers. In this way, chamber matching can be implemented to improve process uniformity across different chambers.

It should be understood that the processing operations disclosed in Figures 6A and 6B need not be performed in any particular order. That is, each signal can be acquired at any time. For example, in one embodiment, the reference signal may be acquired when no processing is taking place in the chamber. This provides a reference signal that is not altered by any electromagnetic radiation emitted by the plasma. However, it should be understood that in some embodiments, the reference signal may be acquired as the plasma impinges in the chamber. In other embodiments, the processing signal may be acquired when the source is turned off. In these embodiments, a pure signal from the plasma can be obtained without any interference from the source light. However, it should be understood that in some embodiments the source light may be on during measurement of the processed signal. Furthermore, it should be understood that one or both of the reference signal and the process signal may be acquired during processing of one or more substrates in the chamber. In this way, the measurement can be called an in situ measurement.

Referring now to FIG. 7 , illustrated is a block diagram of an exemplary computer system 760 for a processing tool in accordance with an embodiment. In one embodiment, computer system 760 is coupled to and controls processing in the processing tool. Computer system 760 may be connected (eg, network connected) to a local area network (LAN), an intranet, an extranet, or other machines on the Internet. Computer system 760 may operate in the capacity of a server or client machine in a client-server network environment, or as a peer machine in a peer-to-peer (or distributed) network environment. Computer system 760 may be a personal computer (PC), tablet computer, set-top box (STB), personal digital assistant (PDA), mobile phone, network application device, server, network router, switch or bridge, or Any machine capable of executing a set of instructions (sequential or otherwise) specifying actions to be taken by the machine. Additionally, although only a single machine is illustrated with respect to computer system 760, the term "machine" shall also be taken to include any collection of machines (e.g., computers) that individually or jointly execute a set (or multiple sets) of instructions. , to perform any one or more of the methods described herein.

Computer system 760 may include a computer program product, or software 722, a non-transitory machine-readable medium having instructions stored thereon that may be used to program computer system 760 (or other electronic device) to perform operations in accordance with embodiments. handle. Machine-readable media includes any mechanism for storing or transmitting information in a form readable by a machine (eg, a computer). For example, machine-readable (eg, computer-readable) media include machine-readable (eg, computer-readable) storage media (eg, read-only memory ("ROM"), random access memory ("RAM") , disk storage media, optical storage media, flash memory devices, etc.), machines (e.g., computers) can read transmission media (electrical, optical, acoustic or other forms of propagation signals (e.g., infrared light signals, digital signals) etc.

In one embodiment, computer system 760 includes system processor 702, main memory 704 (e.g., read only memory (ROM), flash memory, dynamic random access memory such as synchronous DRAM (SDRAM) or Rambus DRAM (RDRAM)). access memory (DRAM, etc.), static memory 706 (e.g., flash memory, static random access memory (SRAM), etc.) and secondary memory 718 (e.g., data storage device), each other via a bus Platoon 730 Communications.

System processor 702 represents one or more general purpose processing devices, such as a microsystem processor, central processing unit, or the like. More specifically, the system processor may be a Complex Instruction Set Computing (CISC) microsystem processor, a Reduced Instruction Set Computing (RISC) microsystem processor, a Very Long Instruction Word (VLIW) microsystem processor, or a processor that implements other instruction sets. A system processor, or a system processor that implements a combination of instruction sets. The system processor 702 may also be one or more special purpose processing devices, such as an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), a digital signal system processor (DSP), or a network system processor. wait. System processor 702 is configured to execute processing logic 726 for performing the operations described herein.

Computer system 760 may further include system network interface device 708 for communicating with other devices or machines. Computer system 760 may also include an image display unit 710 (e.g., a liquid crystal display (LCD), a light emitting diode display (LED), or a cathode ray tube (CRT)), an alphanumeric input device 712 (e.g., a keyboard), a cursor control Device 714 (eg, mouse) and signal generating device 716 (eg, speaker).

Secondary memory 718 may include machine-accessible storage media 731 (or, more specifically, computer-readable storage media) having stored thereon one or more sets of instructions (eg, software 722) that Perform any one or more methods or functions described herein. Software 722 may also reside fully or at least partially within main memory 704 and/or system processor 702 during execution by computer system 760 , which also constitute machine-readable storage media. Software 722 may further be transmitted or received over network 720 via system network interface device 708. In one embodiment, network interface device 708 may operate using RF coupling, optical coupling, acoustic coupling, or inductive coupling.

Although machine-accessible storage medium 731 is shown as a single medium in the exemplary embodiment, the term "machine-readable storage medium" should be taken to include a single medium or multiple media that store one or more sets of instructions ( For example, centralized or distributed databases and/or associated caches and servers). The term "machine-readable storage medium" shall also be deemed to include any medium capable of storing or encoding a set of instructions for execution by a machine and causing the machine to perform any one or more methods. Accordingly, the term "machine-readable storage media" shall be deemed to include, but not be limited to, solid-state memory, and optical and magnetic media.

In the foregoing specification, specific exemplary embodiments have been described. It will be apparent that various modifications may be made without departing from the scope of the following claims. Accordingly, this specification and drawings are to be regarded as illustrative rather than restrictive.

100: Processing tool 105: Chamber 107: Plasma 108: Substrate support 120: Optical sensor 121: Reflector 122: Second housing 123: Opening 124: First housing 125: Lens 126: Tube 132: Fiber optic cable 134: Splitter 135: Fiber optic cable 136: Fiber optic cable 137: Source 138: Sensor 220: Optical sensor 221: Reflector 222: Second housing 223: Opening 224: First housing 225: Lens 226: Tube 227 :Channel 228: Optical path 305: Chamber 306: Membrane 320: Optical sensor 321: Reflector 322: Second housing 323: Opening 324: First housing 325: Lens 332: Fiber optic cable 341: Reference signal 342: Reflection Signal 343: Plasma signal 405: Chamber 420: Optical sensor 421: Reflector 422: Second housing 425: Lens 437: Source 438: Sensor 439: 稜鏡 441: Reference signal 442: Reflected signal 443: Plasma Signal 445: Filter 500: Processing tool 505: Chamber 508: Substrate support 520 _A ~ 520 _E : Optical sensor 660: Processing 661 ~ 663: Operation 670: Processing 671 ~ 673: Operation 702: System processor 704: Main memory 706: static memory 708: system network interface device 710: image display unit 712: alphanumeric input device 714: cursor control device 716: signal generation device 718: secondary memory 720: network 722: software 726 :Processing logic 730:Bus 731:Machine-accessible storage media 760:Computer system

Figure 1 is a cross-sectional view of a chamber with optical sensors through the chamber wall, according to an embodiment.

Figure 2 is a cross-section of a perspective view of an inductor housing according to an embodiment.

3A is a cross-sectional view of an optical sensor through a chamber wall and illustrates the optical path through the sensor housing, according to an embodiment.

3B is a cross-sectional view of an optical sensor after depositing a layer of material over a reflector, according to an embodiment.

4A is a cross-sectional view of an optical sensor with a source and sensor integrated into the sensor housing, according to an embodiment.

Figure 4B is a cross-sectional view of an optical sensor with a filter along an optical path, according to an embodiment.

Figure 5 is a plan view of a processing chamber with an optical sensor array through the chamber wall, according to an embodiment.

Figure 6A is a process flow diagram depicting a process for determining wall conditions or process conditions using optical sensors, according to an embodiment.

Figure 6B is a process flow diagram depicting a process for obtaining a reference signal, according to an embodiment.

7 illustrates a block diagram of an exemplary computer system that may be used with an optical sensor having an optical path through a chamber wall, according to an embodiment.

Domestic storage information (please note in order of storage institution, date and number) without Overseas storage information (please note in order of storage country, institution, date, and number) without

100:Processing Tools

105: Chamber

107:Plasma

108:Substrate support

120: Optical sensor

121:Reflector

122:Second shell

123:Open your mouth

124:First shell

125:Lens

126:Tube

132:Fiber optic cable

134:Separator

135:Fiber optic cable

136:Fiber optic cable

137:source

138: Sensor

Claims (14)

A processing tool that includes: a chamber; and An optical sensor system passes through a wall of the chamber, wherein the optical sensor system includes; a shell; an optical path passing through the housing, wherein the optical path includes a first end in the chamber and a second end outside the chamber; a reflector located at the first end of the optical path; a lens between the reflector and the second end of the optical path; and An opening passes through the housing between the lens and the reflector, wherein the opening is within the chamber. The optical sensor system as described in claim 1 further includes: a light source optically coupled to the lens; and A sensor optically coupled to the lens. The optical sensor system of claim 2, wherein the light source is a single wavelength source. The optical sensor system of claim 2, wherein the light source is a broadband light source. The optical sensor system of claim 2, wherein the light source and the sensor are optically coupled to the lens through a fiber optic cable. The optical sensor system of claim 5, wherein the optical fiber cable includes a splitter. The optical sensor system as described in claim 2 further includes: A bandpass filter located at a location along an optical path between the sensor and the opening. The optical sensor system as claimed in claim 2, wherein the sensor is a spectrometer or a photodiode. The optical sensor system of claim 2, wherein the light source and the sensor are integrated into the housing. The optical sensor system as claimed in claim 1, wherein the housing is transparent. The optical sensor system of claim 1, wherein the reflector is removable. An optical sensing array for a plasma processing chamber, comprising: A plurality of optical sensing systems oriented around a perimeter of the plasma processing chamber, wherein the optical sensing system passes through a wall of the plasma processing chamber, wherein one of the plurality of optical sensing systems Each includes: a housing passing through the wall of the plasma processing chamber; an optical path passing through the housing, wherein the optical path includes a first end and a second end; a reflector located at the first end of the optical path; a lens between the reflector and the second end of the optical path; and An opening passes through the housing within the plasma processing chamber, wherein the opening is between the lens and the reflector. The optical sensing array of claim 12, wherein the plurality of optical sensing systems are configured to provide uniformity data of a plasma condition, a wall condition, or a plasma condition and a wall condition. The optical sensing array of claim 12, wherein the plurality of optical sensing systems are configured to provide chamber drift monitoring.